U.S. patent application number 13/305953 was filed with the patent office on 2012-05-31 for capacitive touch panel.
This patent application is currently assigned to Beijing BOE Optoelectronics Technology Co., Ltd.. Invention is credited to Xiaochuan CHEN, Wei LI, Xiaokun LI.
Application Number | 20120133613 13/305953 |
Document ID | / |
Family ID | 46091678 |
Filed Date | 2012-05-31 |
United States Patent
Application |
20120133613 |
Kind Code |
A1 |
CHEN; Xiaochuan ; et
al. |
May 31, 2012 |
CAPACITIVE TOUCH PANEL
Abstract
Embodiments of the present disclosure provide a capacitive touch
panel capable of simplifying a manufacture process thereof. The
capacitive touch panel comprises a first substrate and a second
substrate provided opposite to each other, wherein a common
electrode and at least two parallel electrode lines are disposed
between the first substrate and the second substrate, at least two
touch electrodes are connected in series by each of the electrode
lines, any two of the touch electrodes connected by a same
electrode line have an area different from each other, varying
sequentially, the touch electrode and the common electrode form a
capacitor, and the electrode line is connected to a touch signal
sensing device. The capacitive touch panel provided by embodiments
of the present disclosure may achieve one-dimensioned
positioning.
Inventors: |
CHEN; Xiaochuan; (Beijing,
CN) ; LI; Wei; (Beijing, CN) ; LI;
Xiaokun; (Beijing, CN) |
Assignee: |
Beijing BOE Optoelectronics
Technology Co., Ltd.
Beijing
CN
|
Family ID: |
46091678 |
Appl. No.: |
13/305953 |
Filed: |
November 29, 2011 |
Current U.S.
Class: |
345/174 ;
200/5A |
Current CPC
Class: |
G06F 3/0443 20190501;
G06F 2203/04103 20130101 |
Class at
Publication: |
345/174 ;
200/5.A |
International
Class: |
G06F 3/045 20060101
G06F003/045; H03K 17/975 20060101 H03K017/975 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 29, 2010 |
CN |
201010571669.8 |
Claims
1. A capacitive touch panel comprising: a first substrate; and a
second substrate provided opposite to the first substrate, wherein
a common electrode and at least two parallel electrode lines are
disposed between the first substrate and the second substrate, at
least two touch electrodes are connected in series along each of
the electrode lines, and any two of the touch electrodes connected
by same one electrode line have areas different from each other;
and each of the touch electrodes and the common electrode form a
capacitor, and each of the electrode lines is connected to a touch
signal sensing device.
2. The capacitive touch panel as in claim 1, wherein the touch
signal sensing device is disposed at an end of each of the
electrode lines.
3. The capacitive touch panel as in claim 1, wherein the parallel
electrode lines extend parallel in a longitudinal or a transverse
direction.
4. The capacitive touch panel as in claim 1, wherein the at least
two touch electrodes connected in series by the same electrode line
have areas sequentially increased or decreased.
5. The capacitive touch panel as in claim 4, wherein along a same
direction, the touch electrodes have areas varying in a same
tendency between two adjacent electrode lines.
6. The capacitive touch panel as in claim 5, wherein the touch
signal sensing device is connected to an end of the electrode line
closer to the touch electrode that has a relative larger area.
7. The capacitive touch panel as in claim 4, wherein along a same
direction, the touch electrodes have areas varying in a reverse
tendency between two adjacent electrode lines.
8. The capacitive touch panel as in claim 1, wherein each electrode
line and the at least two touch electrode connected in series by
the electrode line are of an integral structure.
9. The capacitive touch panel as in claim 1, wherein the common
electrode and the touch electrodes are provided on the first
substrate and the second substrate, respectively, and a cavity is
formed between the first substrate and the second substrate.
10. The capacitive touch panel as in claim 1, wherein the common
electrode and the touch electrodes both are provided on the first
substrate or the second substrate, and an insulating layer is
formed between the first substrate and the second substrate.
11. The capacitive touch panel as in claim 1, wherein the common
electrode, the electrode line and the touch electrode are formed of
a transparent conductive material.
12. The capacitive touch panel as in claim 11, wherein the
transparent conductive material comprises nano indium tin
oxide.
13. The capacitive touch panel as in claim 1, wherein the touch
electrode has a shape of rhombus, rectangular, circular,
elliptical, or triangle.
14. A display device comprising: the capacitive touch panel
according to claim 1; and a display panel, wherein the capacitive
touch panel are provided on the display panel.
15. The display panel according to claim 14, wherein the display
panel comprises liquid crystal display (LCD) panel, organic
light-emitting display (OLED) panel, light-emitting display panel,
or plasma display panel.
16. The display panel according to claim 14, wherein the capacitive
touch panel is attached to the display panel or integratedly formed
with the display panel.
Description
BACKGROUND
[0001] Embodiments of the disclosed technology relate to a
capacitive touch panel.
[0002] Capacitive touch panels are a relatively popular type of
existing touch panels. A capacitive touch panel works as
follows.
[0003] Row electrodes and column electrodes are disposed in the
capacitive touch panel, as shown in FIG. 1 and FIG. 2. The row
electrodes and the column electrodes are insulated from each other,
and they each faint a capacitor together with a common electrode.
As a human body is conductive, touching a surface of the capacitive
touch panel with a finger results in a coupling capacitance formed
between the finger and row and column electrodes of the touch
panel. Due to the change of capacitance at the touching point,
currents are respectively induced in the row and column electrodes,
flowing towards the touching point. The induced current each has
intensity inversely proportional to a distance between the finger
and a boundary of the touch panel. Positions of the touching point
can be accurately determined by measuring of the induced currents
with sensors disposed at both ends of the row and column
electrodes.
[0004] In practicing the above capacitive touch panel, the
inventors has found that there are at least following problems.
[0005] Most of the existing capacitive touch panels employ a
structure of such row and column electrodes and determine the
positions of a touching point by sensing changes in currents or
change of pulse signals over the row and column electrodes.
However, such structure of the capacitive touch panel needs to
fabricate a plurality of layers, such as a row electrode layer, a
column electrode layer, a common electrode layer, and insulating or
protective layers between various conductive layers. Thus, the
fabrication process is complicated, and especially, wiring is
relatively difficult in a small-sized touch panel.
SUMMARY
[0006] An embodiment of the present disclosure provides a
capacitive touch panel capable of simplifying a manufacture process
for forming the touch panel.
[0007] An embodiment of the disclosed technology provides a
capacitive touch panel comprising a first substrate; and a second
substrate provided opposite to the first substrate, wherein a
common electrode and at least two parallel electrode lines are
disposed between the first substrate and the second substrate, at
least two touch electrodes are connected in series along each of
the electrode lines, and any two of the touch electrodes connected
by same one electrode line have areas different from each other;
and each of the touch electrodes and the common electrode form a
capacitor, and each of the electrode lines is connected to a touch
signal sensing device.
[0008] Another embodiment of the disclose technology provides a
display device comprising: the above-described capacitive touch
panel; and a display panel, wherein the capacitive touch panel are
provided on the display panel.
[0009] In the capacitive touch panel according to an embodiment of
the present disclosure, a plurality of touch electrodes having an
area different from one another may be disposed on same one
electrode line. In this case, since touch points correspond to the
touch electrodes having different areas, the change in capacitance
at the touched touch point due to a coupling capacitance occurred
between the finger and the touched touch electrode during a
touching operation is different from that at other touch points.
Further, the intensity of an electric signals detected by the touch
signal sensing device connected to the respective touch electrode
line are also different from each other. Thus, a specific touch
point can be determined on the touch electrode line 4 according to
the intensity of the detected electric signals. In addition, since
location of each of the touch electrode lines is fixed, information
about location of the touch electrode lines may be stored in
advance in a controlling module of the capacitive touch panel so as
to determine the location of the touch point accurately and
quickly. With the capacitive touch panel provided by the above
embodiments, positioning of the touch point may be achieved so long
as one layer of the electrode lines is provided and the electrode
lines extend in a same direction. Accordingly, in the manufacture
process for the capacitive touch panel, the electrode lines in the
other direction can be eliminated, thereby simplifying the
manufacture process for the capacitive touch panel.
[0010] Further scope of applicability of the present disclosure
will become apparent from the detailed description given
hereinafter. However, it should be understood that the detailed
description and specific examples, while indicating preferred
embodiments of the disclosure, are given by way of illustration
only, since various changes and modifications within the spirit and
scope of the disclosure will become apparent to those skilled in
the art from the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The drawings, which are necessary for following description
of embodiments of the present disclosure, will now be described
briefly in order to more fully disclose embodiments of the present
disclosure or approaches of the prior art. It is to be easily
understood by those skilled in the art that the drawings show
merely some embodiments of the present disclosure and some other
drawings may be obtained on the basis of the following drawings
without any mental work.
[0012] FIG. 1 is a schematic plan view showing structure of an
existing capacitive touch panel.
[0013] FIG. 2 is a schematic plan view showing structure of another
existing capacitive touch panel.
[0014] FIG. 3 is a schematic plan view showing structure of a
capacitive touch panel according to an embodiment of the present
disclosure.
[0015] FIG. 4 is a cross sectional view of a capacitive touch panel
taken along a line A-A in FIG. 3.
[0016] FIG. 5 is a schematic view showing structure of a capacitive
touch panel while it is not touched, according to an embodiment of
the present disclosure.
[0017] FIG. 6 is a schematic view showing structure of a capacitive
touch panel while it is being touched, according to an embodiment
of the present disclosure.
[0018] FIG. 7 is a schematic plan view showing structure of a
capacitive touch panel according to another embodiment of the
present disclosure.
DETAILED DESCRIPTION
[0019] Embodiments of the present disclosure will now be described
more fully and clearly hereinafter with reference to the
accompanying drawings in which the embodiments of the present
disclosure are shown. It is to be recognized by those skilled in
the art that the embodiments set forth herein is merely a part
rather than all of the present disclosure. All other embodiments
that can be obtained by those skilled in the art on the basis of
the disclosed embodiments without any mental work fall within the
scope of the present disclosure.
[0020] In order to simplify a process for manufacturing a
capacitive touch panel, an embodiment of the present disclosure
provides a capacitive touch panel as below.
[0021] FIG. 3 is a schematic plan view showing structure of a
capacitive touch panel according to an embodiment of the present
disclosure; FIG. 4 is a cross sectional view of the capacitive
touch panel taken along a line A-A in FIG. 3. With reference to
FIG. 3 and FIG. 4 in combination, the embodiment of the present
disclosure provides a capacitive touch panel comprising a first
substrate 1 and a second substrate 2 disposed opposite to each
other. A common electrode 3 and at least two parallel electrode
lines 4 are provided between the first substrate 1 and the second
substrate 2; the common electrode 3 and the at least two parallel
electrode lines 4 are provided on the second and the first
substrates, respectively. At least two touch electrodes 5 are
connected in series by each of the electrode lines 4, and any two
touch electrodes 5 connected by a same electrode line 4 have an
area different from each other. The touch electrode 5 each forms a
capacitor along with the common electrode 3. The electrode line 4
is connected with a touch signal sensing device 6.
[0022] For example, the touch signal sensing device 6 may be
disposed at an end of each electrode line 4 and positioned at a
same side of the capacitive touch panel as the electrode lines
4.
[0023] FIG. 3 shows a layout of the electrode lines 4 that extend
parallel in a longitudinal direction. However, the layout of the
electrode lines 4 is not limited thereto. In addition to the
longitudinal arrangement, the electrode lines 4 may also be
arranged in a transverse or inclined direction. It is preferred in
current embodiment that the electrode lines 4 extend parallel to
each other in the longitudinal or transverse direction since the
touch electrodes 5 connected in series by the respective electrode
lines 4 may be arranged more regularly.
[0024] In the forgoing capacitive touch panel, a plurality of touch
electrodes 5 having an area different from one another are disposed
on same one electrode line 4. In this case, since different touch
points correspond to the touch electrodes 5 having different
surface areas, the change in capacitance at one touch point due to
the coupling capacitance occurred between the finger and the touch
electrode, which is touched during a touching operation, is
different from that at the other touch points. Further, the
intensity of the electric signals detected by the touch signal
sensing devices 6 connected to the respective touch electrode lines
4 are also different from each other. Thus, a specific touch point
can be determined on the touch electrode line 4 according to the
intensity of the detected electric signal. In addition, in an
example, since location of each of the touch electrode lines 4 is
fixed, information about location of the touch electrode lines 4
may be stored in advance in a controlling module of the capacitive
touch panel, so that the location of the touch point can be
determined accurately and quickly.
[0025] In particular, as shown in FIG. 5, when the capacitive touch
panel is not touched, the touch electrode 5 and the common
electrode 3 form a capacitor that is in a static equilibrium state.
When a finger 7 is touching the surface of the capacitive touch
panel, as shown in FIG. 6, a coupling capacitance occurs between
the finger 7 and one touch electrode 5 such that the capacitance
between the touch electrode 5 and the common electrode 3 varies.
Further, it may be understood that since the contact area between
the finger and the capacitive touch panel is larger than an average
area of the touch electrodes 5, the change amount in capacitance is
in association only with the area of the touched touch electrode 5.
During the touching operation, a touch electrode 5 having a
relatively larger area has a larger change in capacitance and thus
generates a larger induced current; on the other hand, a touch
electrode 5 having a relatively smaller area has a smaller change
in capacitance and thus generates a smaller induced current.
[0026] The touch signal sensing devices 6, which are connected to
the touch electrode lines 4, respectively, can detect intensity of
the induced currents and output the detected current values to the
control module of the capacitive touch panel. The control module
can determine location of the touch point on the touch electrode
line 4 according to a correspondence relationship between the
current value and the coordinate (e.g., the relationship between
the current I and the coordinate Y shown in Table 1 below) that is
stored therein in advance. Meanwhile, with reference to location
information of the touch electrode lines 4 stored therein, the
control module can determine the exact location of the touch point
on one of the touch electrode lines 4.
TABLE-US-00001 TABLE 1 Current I.sub.1 I.sub.2 . . . I.sub.n
Coordinate Y.sub.1 Y.sub.2 . . . Y.sub.n
[0027] The data in the table 1 is obtained for the case where the
touch electrode lines 4 extend parallel in the longitudinal
direction. At this time, a longitudinal coordinate of the touch
point on the touch electrode line 4 may be obtained according to
the current detected by the touch signal sensing device 6 connected
to this touch electrode line 4. Meanwhile, the exact location of
the touch point on the capacitive touch panel may be obtained with
reference to the transverse coordinate of the touch electrode line
4 stored in the control module of the capacitive touch panel.
[0028] The data in the above table 1 can be obtained through tests
before the capacitive touch panel is put into use, and the data is
stored for determination of the touch point in operation of the
capacitive touch panel.
[0029] It is to be understood that the embodiments of the present
disclosure are not limited to use the induced current to determine
location of the touch point. The touch signal sensing device 6 may
serves to detect other forms of electric signals, such as voltage,
pulse signal, or the like. However, the following embodiments will
still take current as an example to describe the capacitive touch
panel according to the embodiment of the present disclosure.
[0030] Still referring to the capacitive touch panel shown in FIG.
3, the at least two touch electrodes 5 that are connected in series
by same one touch electrode line 4 may have areas sequentially
increased or decreased. With reference to the structure of the
capacitive touch panel shown in FIG. 3, in particular the touch
electrodes 5 connected in series by same one touch electrode line 4
have areas sequentially increased or decreased from the top to the
bottom in the longitudinal direction.
[0031] Provided that the at least two touch electrodes 5 connected
in series by same one touch electrode line 4 have different areas,
the touch signal sensing device 6 can detect electric signals with
different intensity, and therefore the location of the touch point
can be determined according to the different intensity of the
detected electric signals. In the present disclosure, it is
preferable to set a rule for varying of area of the touch
electrodes 5 connected in series by the same touch electrode line 4
such that the current induced while touching the touch electrodes 5
shows a corresponding regularity. With such a configuration, it is
possible to simplify the manufacture process for the capacitive
touch panel and improve accuracy of positioning of the touch
point.
[0032] In addition, as to the touch electrodes 5 disposed on two
neighboring electrode lines 4, area change thereof may have a same
tendency in a same direction, as shown in FIG. 3, or a reverse
tendency in the same direction, as shown in FIG. 7.
[0033] In the structure shown in FIG. 3, when the effect of the
resistance of the touch electrode line 4 on intensity of the
induced current is taken into consideration, it may be preferable
that the touch signal sensing device 6 is disposed at an end of the
touch electrode line 4 closer to the touch electrode 5 that has a
relatively large area. As such, in a touching operation, the touch
electrode 5 with a relative large area generates a relative high
induced current while the resistance between the touch electrode 5
and the touch signal sensing device 6 is low, and the touch
electrode 5 with a relative small area generates a relative low
induced current while the resistance between the touch electrode 5
and the touch signal sensing device 6 is large. In this case,
difference between currents in relation to various touch electrodes
5 detected by the touch signal sensing device 6 may be further
increased, and therefore accuracy of positioning (position
determination) of the touch point can be further improved.
[0034] If the resolution of the capacitive touch panel decreases as
the surface areas of the touch electrodes 5 increase sequentially,
the configuration as shown in FIG. 7 can be employed. Since the
touch electrodes 5 have a varying tendency reverse between two
neighbouring electrode lines 4, the interval between the two
neighboring electrode lines 4 can be decreased as compared with
that shown in FIG. 3 and only need to be greater than (maximal
width of the touch electrode+minimal width of the touch
electrode)/2. In addition, when an induced current corresponding to
a touch electrode on an electrode line is too small to determine
the position of the touch point, a current detected on an adjacent
electrode line may be used as assistant or reference.
[0035] In the above-described capacitive touch panel, each touch
electrode line and the at least two touch electrode connected in
series by the electrode line are preferably formed as an integral
structure so that they can be fabricated at a same level in the
manufacture process, thereby simplifying the manufacture
process.
[0036] In the above-described capacitive touch panel, the common
electrode, the electrode line and the touch electrode may all be
made of a transparent material, for example, nano indium tin oxide
(nano-ITO). Space between the first substrate and the second
substrate may form a cavity or be further filled with a transparent
insulation material such that the common electrode and the touch
electrode can form a capacitor while transmittance of light
therethrough is not substantially affected.
[0037] In the case of cavity, the common electrode and the touch
electrode may be disposed on the first substrate and the second
substrate, respectively; in the case of filling a transparent
insulation material, the common electrode, the transparent
insulation material and the touch electrode may be formed
sequentially on the first substrate or the second substrate.
[0038] In the forgoing embodiments, the shape of the touch
electrodes is not limited. In addition to the rhombus as shown in
FIG. 3, the touch electrode may also have a rectangular shape, a
circular shape, an elliptical shape, a triangle shape or any other
planar shape.
[0039] In the forgoing embodiments and drawings showing embodiments
of the present disclosure, the capacitive touch panel according to
embodiments of the disclosure is described in terms of longitudinal
extension of the electrode line. However, as discussed above, the
capacitive touch panel according to embodiments of the disclosure
may have the electrode lines extending parallel in the transverse
direction. Such structure is substantially the same as that of the
longitudinal arrangement except that the direction is different,
and thus a description thereof is omitted.
[0040] With the capacitive touch panel provided by the above
embodiments, positioning of the touch point can be achieved so long
as one layer of the electrode lines is provided and the electrode
lines extend in a same direction. Accordingly, in the manufacture
process for the capacitive touch panel, the electrode lines in the
other direction can be eliminated, thereby simplifying the
manufacture process for the capacitive touch panel. In addition,
the present disclosure may achieve one-dimensioned positioning, and
the touch signal sensing device may not be used in another
dimension, thereby reducing number of the used touch signal sensing
devices and thus the cost.
[0041] Another embodiment of the disclosure provides a display
device, which comprises any of the above-described capacitive touch
panel and a display panel, and the capacitive touch panel are
provided on the display panel by, for example, attaching to the
display panel or integratedly formed with the display panel. The
examples of the display panel include liquid crystal display (LCD)
panel, organic light-emitting display (OLED) panel, light-emitting
display panel, plasma display panel, and the like. In the case
where the capacitive touch panel is integratedly formed with the
display panel, the upper surface of the display panel is used as a
substrate of the capacitive touch panel.
[0042] While the present disclosure has been shown and described
with regard to certain preferred embodiments, it is to be
understood that modifications in form and detail will no doubt be
developed by those skilled in the art upon reviewing this
disclosure. It is therefore intended that the following claims
cover all such alterations and modifications that nevertheless
include the true spirit and scope of the inventive features of the
present disclosure.
* * * * *